Power supply



FIG. 1 is a perspective view of a power supply showing my design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a back elevational view thereof;

FIG. 4 is an elevational view thereof from the right side;

FIG. 5 is an elevational view thereof from the left side;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The power cord is shown broken away throughout the drawing figures to indicate indeterminate length. 

The ornamental design for a power supply, as shown and described. 